Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation

{
  "id": "1c58c3cac6985ccf07e3f07c308bff3fe579b63845b9689f984abc87dae42f72",
  "url": "https://osv.dev/vulnerability/CVE-2026-104048",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Sssd: sssd: authorization bypass via cross-domain username collision in hbac evaluation",
    "summary": "A flaw was found in SSSD. In trust-enabled identity management environments, SSSD evaluates Host-Based Access Control (HBAC) rules by stripping domain qualifiers and comparing only short usernames. An authenticated user in a trusted domain who shares the same username as an authorized local account can bypass access policies and gain unauthorized access to protected services or hosts.",
    "evidence": "osv:CVE-2026-104048",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-104048",
      "aliases": [
        "CVE-2026-104048"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/sssd/sssd",
              "type": "GIT",
              "events": [
                {
                  "introduced": "1a1cf163b78ff4768cc8bfc1e631171bc021e2fe"
                },
                {
                  "last_affected": "1a1cf163b78ff4768cc8bfc1e631171bc021e2fe"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:fedoraproject:sssd:2.12.0:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "2.12.0"
                      },
                      {
                        "last_affected": "2.12.0"
                      }
                    ],
                    "source": "CPE_STRING"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.12.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-104048.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:33.819823278Z",
      "provider": "osv",
      "references": [
        "https://access.redhat.com/downloads/content/package-browser/",
        "https://access.redhat.com/security/cve/CVE-2026-104048",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104048.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-104048",
        "https://bugzilla.redhat.com/show_bug.cgi?id=2478613"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-1025"
        ],
        "cna_assigner": "redhat",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/104xxx/CVE-2026-104048.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-104048",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 501136,
  "published_at": "2026-10-06T19:34:25.863+00:00"
}